Also known as: 概念图
Incomplete artwork or ancillary reference materials used in the production of a work, especially anime. This is almost always Official Art, with the exception of production work of individual doujin animations.
This includes Unfinished and Making-Of materials such as:
- Works drawn on Animation Paper to be used as with a Peg Bar, or featuring Trim Marks for later editing
- Color Traces
- Partially Colored art (when a reference or a piece of pre-production artwork)
- Key Frames
- Animatics (very rough pre-production animations)
- Photo (Medium)s or Scans of physical Cels used in a traditionally animated work
As well as production references such as:
- Storyboards
- Reference Sheets
- Information Sheets
- Production Notes
- Color Guides
- Official Height Charts and Costume Charts
- Promotional Art used in the advertisement of a work